城市轨道交通大直径盾构隧道若干关键技术  

Key Technologies for the Application of Large Diameter Shield Tunnel in Urban Railway

作　　者：戴志仁[1] 王俊[1] 胡瑞青 DAI Zhiren;WANG Jun;HU Ruiqing(China Railway First Survey and Design Institute Group Co.Ltd,Xi’an,Shaanxi 710043,China)

机构地区：[1]中铁第一勘察设计院集团有限公司,西安710043

出　　处：《铁道工程学报》2021年第6期75-81,共7页Journal of Railway Engineering Society

基　　金：2016年度陕西省重点科技创新团队计划项目-西安地铁修建关键技术研究创新团队(2016KCT-07)。

摘　　要：研究目的:近年来,随着城市轨道交通列车运行速度不断提高,大直径盾构隧道应用越来越普遍,但设计与施工大部分仍沿袭常规6 m直径盾构隧道理念,经常面临开挖面稳定性难以控制、小半径曲线施工困难、管片端部裂缝或角部碎裂几率增大、管片拼装难度大、成型隧道质量难以控制、盾构隧道扩挖风险加剧、隧道内部变形监测数据难以直接反映隧道安全状态等难题,本文对上述主要问题展开研究,以期提高城市轨道交通大直径盾构隧道整体建造水准。研究结论:(1)为有效应对大直径盾构隧道千斤顶反力作用于管片端部的局部荷载,管片端部一定高度范围内配筋需要进行加强,减小管片裂缝几率;(2)管片纵缝设置的半圆槽与导向杆可在管片拼装阶段起到导向的作用,环缝设置的嵌锁系统可有效减少管片错台与踏步几率,提高成型隧道质量;(3)以正常使用阶段管片裂缝为控制标准,明确了一定配筋率情况下管片衬砌所能承受的最大附加变形(椭圆率),进一步提出了基于洞内变形监测数据的隧道安全计算模型;(4)基于PBA法的大直径盾构隧道扩挖技术,可实现城市轨道交通先隧后站需求,极大地增加工筹的灵活性,缓解重难点车站工期压力;(5)盾构选型与关键设备的选取原则、小半径曲线掘进、盾构刀盘选择与常压换刀等关键技术,可进一步增强大直径盾\构隧道实施水准;(6)本研究成果可为大直径盾构隧道在城市轨道交通中的大范围运用提供参考。Research purposes: In recent years, large diameter shield tunnel is more widely used in urban railway, especially for the constant increase in train speed. However, the relevant design and construction methods are still based on the concept of the common 6 m diameter shield tunnel. And many problems will result, such as the difficulty in the stability control of excavation face, the difficulty in the construction of small curves, cracks and fragmentation in segment corner, the difficulty in segment assembling and the quality control of built tunnel. And the risk of shield tunnel enlargement will be increased, and the monitoring deformation data can hardly directly reflect the safety state of shield tunnel. Based on the study of the main problems mentioned above, the overall construction level of large diameter shield tunnel in urban railway can be correspondingly promoted.Research conclusions:(1) In order to effectively deal with the local load applied to the segment end by the counterforce of the jack of large diameter shield tunnel, the reinforcement at the segment end within a certain height range needs to be strengthened to reduce the crack probability of the segment.(2) The semicircle groove and guide bar in the longitudinal joint can play a guiding role in segment assembly stage, and the segment assembling quality can be improved with the locking system between circular joint.(3) Based on the control standards of segment cracks, the biggest deformation that can be endured by certain reinforcement is made clear, and the calculation mode for tunnel safety based on deformation monitoring data is put forward.(4) The enlargement of large diameter shield tunnel with PBA method can realize the expansion technology of metro station based on shield tunnel, enhance flexibility of project planning greatly, and alleviate the pressure of construction period correspondingly.(5) The key technologies such as selection principle of shield and key equipment, small curves tunnelling construction, the selection of shield cutti

关 键 词：大直径盾构隧道 开挖面稳定 管片设计 基于变形数据的安全管控 先隧后站 掘进施工 

分 类 号：U2[交通运输工程—道路与铁道工程]